Panel light modules



Dec. 31, 1968 E. P. cHEsLocK PANEL LIGHT MODULES Filed May 19. 1965 Sheet l of 4 Dec. 31, 1968 E. P. cHl-:sLocK .BAW-713 PANEL LIGHT MODULES Filed may 19, 196s sheet 2 NVENTORS. /PEs' \3|4 EDWARD P. CHESLOCK BY Mew, /ndfz,

ATTQRNEYS Dec. 31, 1968 E. P. cr-lEsLocK 3,49f713 PANE'L LIGHT MODULES Filed may 19. 196s Sheet -71. 0f 4 LU E (Dm n a: .F3 LLJ f2 F' mw 2 @f J cv U) @4 12D] l@ Q g -1 3 l J Q J o UJIO INVNTRS. in@ EDWARD P cHEsLocfK INTERSECTION C ATTORNEY E. P. CHESLOCK PANEL LIGHT MODULES Dec. 31, 196s Sheet rma uay 19. 196s INVENTORS.

EDWARD F? CHESLOCK BY MW,

ATTORNEYS United States Patent 3,419,713 PANEL LIGHT MODULES Edward P. Cheslock, Newtown Square, Pa., assignor to E. W. Bliss Company, Canton, Ohio, a corporation of Delaware Filed May 19, 1966, Ser. No. 551,308 14 Claims. (Cl. 240--1.2)

ABSTRACT F THE DISCLOSURE A panel light module, adapted to be employed with a display panel, for providing a fvisual display of traffic locations. The panel light module has an outer sleeve which surrounds :a polyester encapsulated bulb, and which is constructed of `a material having light reflective and heat dissipating characteristics.

This invention relates to panel light modules particularly applicable for use with a `display panel used in conjunction with routing aircraft ground traffic through an airports runway and taxiway intersection network, as described and claimed in copending United States ap plication, Ser. No. 565,462, tiled July 5, 1966, which is a continuing Vapplication of application, Ser. No. 551,679, tiled May 20, 1966, now abandoned, assigned to the same assignee as the present invention, and which application is incorporated herein by reference.

This invention, however, is not limited to use with the display panel in that application and may, for example, be used in conjunction with any display panel requiring panel lights.

Display panel lights known heretofore include lamp bulbs which protrude from the face of a display panel. Frequently, however, it is desired that a `display panel face be substantially flat with no objects, such as bulbs, protruding therefrom. Accordingly, bulbs are frequently mounted in the rear side of a display panel so that light may be transmitted through the face of the panel. A display panel for such rear mounted bulbs must include structure for mounting the bulbs. Previous to the present invention, such mounting structure has normally taken the form of a standard bulb socket mounted to the panels rear side within a panel aperture. However, when the bulbs filament has broken after prolonged use, it is quite difficult to remove the bulb from the panel. The removal procedure may, for example, require removal of the bulb socket lfrom the panel before the bulb can be :removed and replaced with a new bulb, after which the socket is remounted to the panel. Thus, replacement of light bulbs is a time consuming, tedious process, resulting in considerable -downtime in the operation of the display panel.

The noted disadvantages, and others, of previous display panel lights is overcome by the present invention which provides a display panel light module which may be easily removed from a panel and replaced with a like module, resulting in minimum `downtime of a display panel when a light bulb in a module must be replaced.

In accordance with the present invention, the panel light module includes: a sleeve having at least one light bulb located therein for transmitting light through one end of the sleeve; and, wherein the light bulb is embedded in polyester within the sleeve in such a manner that the polyester supports the bulb in place in the sleeve.

ICC

In accordance with a still further aspect of the invention, the sleeve serves both as a light reflector and a heat sink, for `dissipating heat generated by the bulb.

Still further in accordance with the invention, the sleeve is `divided into two compartments by a light blocking divider, with the polyester in each compartment being color dyed.

Further in accordance with the invention, the divider extends for a distance less than that of the sleeve, detining two short compartments with the polyester in one compartment being dyed a different color than that in the other compartment and the polyester lling the remaining length of the sleeve being clear.

The primary object of the present invention is to provide a display panel light module which is simple in construction and economical to manufacture.

Another object of the present invention is to provide a light module which does not require standard bulb sockets for supporting light bulbs.

A still further object of the present invention is to provide a light module having light bulb supporting means which also serves as a light lter and lens.

The foregoing and other objects and advantages of the invention will become apparent from the following description of the preferred embodiment of the invention as read in connection with the accompanying drawings, in which:

FIGURE 1 is a perspective view illustrating a display panel;

FIGURE 2 is a plan view illustrating the face of the display panel;

FIGURE 3 is a sectional view of the display taken along line 3-3 in FIGURE 2 looking in the direction of the arrows;

FIGURE 4A is a sectional view of a detector light module constructed in accordance with the invention;

FIGURE 4B is a plan view of the detector light module illustrated in FIGURE 4A;

FIGURE 5A is a sectional view of a program light module constructed in accordance with the invention;

FIGURE 5B is a plan view of the program light module illustrated in FIGURE 5A;

FIGURE `6A is a sectional view of an alarm-intersection light module -constructed in accordance with the invention;

FIGURE 6B is a plan view of the alarm-intersection light module illustrated in FIGURE 6A;

FIGURE 7 is a sectional view of the display panel taken along line 7-7 in FIGURE 2 looking in the direction of the arrows;

FIGURE 8 is an illustration of an airports actual runway and taxiway intersection network;

FIGURE 9 is a front elevational view of an intersection traffic signal;

FIGURE 10 is a rear elevational View of they traffic signal illustrated in FIGURE 9; and

FIGURE ll is a functional block diagram.

Referring now to the drawings, wherein the showings are for the purpose of illustrating a preferred embodiment of the invention and not for purposes of limiting same, FIGURE 1 illustrates a display panel DP having a graphical representation on the panel face of an airports runway and taxiway intersection network, and a magnetic stylus S which, as will be described in greater detail herenafter, is used by a traffic director for tracing a programmed route on the display panels network. The programmed route is representative of a desired route to be followed by an aircraft through the airports actual runway and taxiway intersection network, illustrated in FIG- URE 8.

DISPLAY PANEL The display panel DP graphically illustrates the airports actual taxiway and runway intersection network, including two typical intersections B and C, located as shown in FIGURE 2 with respect to north, south, west and east directions. Each intersection has a plurality of intersection arms extending outwardly from the intersection. Intersection C has north, south, east and west intersection arms and intersection B has a west intersection arm interconnecting with the east intersection arm of intersection C, an east intersection arm and a southwest intersection arm. These intersections and intersection arms correspond with the actual intersections and intersection arms shown in FIGURE 8.

An aircraft detector light module DL for each intersection arm is located in the panel arm adjacent a panel intersection. As will be described in greater detail hereinafter with respect to FIGURES 4A and 4B, each aircraft detector light module DL includes two portions, detector light in DLI and detector light out DLO. Detector light in DLI serves, when energized, to indicate to the traic director that an aircraft has been detected on the actual intersection arm (FIGURE 8) and is heading toward the intersection. Similarly, detector light out DLO represents, when energized, that an aircraft has been detected on the actual intersection arm (FIGURE 8) and is heading away from the intersection.

A program light module PL is associated with each intersection arm and located in the panel intersection adjacent its associated arm. As will be described in greater detail hereinafter with respect to FIGURES 5A and 5B, each program light PL includes two portions, a program light enter portion PLE and a program light leave portion PLL. Program light portion PLE serves, when energized, to visually remind the traffic director that a program has been entered for a vehicle to enter the actual intersection from the associated intersection arm. Similarly, program light portion PLL serves, when energized, to visually remind the traffic director that a program has been entered for an aircraft to leave the actual intersection and proceed into the associated intersection arm.

At the center of each panel intersection there is provided a composite alarm-intersection light module AL-DLC, `described in greater detail hereinafter with reference to FIGURES 6A and 6B. The intersection light DLC serves, when energized, to visually indicate to the traic director that the actual intersection, see FIGURE 8, is occupied by an aircraft. The alarm light AL serves, when energized, to alert the traffic director by flashing on and off that an alarm condition exists, as will be discussed in greater detail hereinafter.

Each panel intersection arm is provided with two magnetic reed program `switches PS1 and PS2, with the former being spaced further from the associated intersection than the latter, as illustrated in FIGURE 2. In addition, each panel intersection arm includes a magnetic reed program erase switch PES located at a point spaced further from the associated intersection than switch PS1. Spaced still further from the intersection than switch PES, and located at a point spaced transversely from the intersection arm, there is provided a magnetic reed detector erase switch DES.

As illustated in FIGURES 3 and 7, the display panel DP preferably takes the form in cross-section of three sandwiched plastic sheets, including a top sheet 300, an intermediate sheet 302 and a bottom sheet 304. The top sheet 300 is preferably sandblasted and opaque and has a cut out portion defining a groove 306. The groove 306, in turn, denes the panels runway and taxiway intersection network, as is best shown in FIGURE 2. As shown in FIGURE 7, groove 306 also serves as a guide folr the piassage of the magnetic stylus S as the traffic director traces the stylus through the panels runway and taxiway intersection network. Groove 306 is particularly advantageous for facilitating movement of the stylus S when tracing turn routes, for example, a turn route from the west arm to the south arm of intersection C, illustrated in FIGURE 2, as opposed to tracing a straight ahead route.

The program light module PL, detector light module DL and magnetic reed switches PS1, PS2, PES and DES for each intersection arm are preferably mounted on a printed circuit board and secured in corresponding cut out portions to bottom sheet 304 so that the modules are located directly beneath groove 306, and that the magnetic reed switches PS1, PS2 and PES are located directly beneath groove 306 and positioned as indicated in FIG- URES 2 and 7. The detector erase switch DES is also located beneath sheet 302 but is spaced transversely away from groove 306, as illustrated in FIGURE 2. Each composite alarm-intersection light module AL-DLC is also mounted beneath sheet 302 directly `beneath the center of a panel intersection, as illustrated in FIGURE 2.

The intermediate sheet 302 is translucent so that light from light modules PL, DL and composite light module AL-DLC may be transmitted upwardly through the sheet. Preferably, sheet 302 exhibits a light transmission characteristic on the order of 70% to permit observation of light from the light modules, while prohibiting observation of the magnetic reed switches PES, PS1 and PS2.

The magnetic reed switches PES, PS1, PS2 and DES may take the form such as that illustrated in FIGURE 7, wherein switch PES is shown as a normally open switch having a stationary contact arm 308 carrying an electrical contact 310 at a free end thereof, and a movable contact arm 312 carrying an electrical contact 314 of magnetic material at a free end thereof. Contact arm 312 is resiliently biased so that contact 314 is normally spaced both mechanically and electrically from contact 3.10. The contacts are enclosed by a glass envelope 316, to protect the contacts from damage and dust conditions. Envelope 316 is mounted so that contacts 310 and 314 are located directly beneath groove 306 with contact 310 being located closer to sheet 302 than is contact 314. In this manner, as stylus S traces a programmed route through groove 306 the magnetic eld of the stylus attracts the magnetic material of contact 314, so that contact 314 mechanically and electrically engages contact 310, closing switch PES. Magnetic reed switches PS1 and PS2 are mounted in the same manner as is switch PES. Detector erase switch DES, however, is mounted at a point spaced transversely away from groove 306, as shown in FIG- URE 2, so that it is not actuated by a stylus S tracing a programmed route through groove 306. Instead, switch DES must be actuated by removing the stylus from groove 306 and placing the stylus on the top surface of sheet 300 immediately above switch DES, for purposes as will be explained in greater detail hereinafter.

The magnetic switches are preferably mounted as close together as possible to reduce the size of the display panel, but the switches must be spaced apart by a sufficient distance that only one switch is actuated by stylus S at any one time. If desired, the magnetic reed switches may be mounted in a vertical plane, as opposed to the horizontal plane illustrated in FIGURE 7, to further reduce the size ofthe display panel.

LIGHT MODULES In accordance with the present invention, each panel light module, FIGURES 4A, 4B, 5A, 5B, 6A and 6B, includes two or three miniature, low voltage electric light bulbs 318. Each bulb is completely embedded in a dyed, high temperature resistant polyester 320. Polyester 320 serves at least three functions; namely, as a mounting for each bulb, as a filter, and as a lens. The polyester 320 exhibits sufficient high temperature resistant characteristics so that it will not melt and/or break apart due to heat generated by an embedded bulb which, for example, is energized by approximately 6 volts. The polyester 320 is encapsulated by an aluminum cylindrical sleeve 322 which serves as a light reflector and as a heat sink to dissipate heat generated by the bulbs.

Each detector light module DL, FIGURES 4A and 4B, includes a light blocking divider 324 extending for a length equal to that of sleeve 322 and separating the sleeve into two compartments 326 and 328, each filled with polyester 320. The polyester 320 in compartments 326 and 328 is preferably dyed yellow so that a yellow signal light is transmitted through the polyester when bulbs 318 are energized. The upper surface 330 of detector light module DL is roughened for a diffusing effect and masked to provide two signal light portions DLl and DLO, each having a distinct directional configuration in the form of a triangular shaped arrowhead as shown in FIGURE 4B. Light portions DLI and DLO are oriented back to back so that the point, i.e., the 90 apex, of each arrowhead points in an opposite direction from that of the other arrowhead.

Each program light module PL, FIGURES 5A and 5B, includes a light blocking divider 332 extending for a length equal to that of sleeve 322 and separating the sleeve into two compartments 334 and 336, each filled with polyester 320. Polyester 320 in compartments 334 and 336 is preferably dyed green so that a green signal light is transmitted through the polyester when bulbs 318 are energized. The upper surface 338 of program light module PL is roughened for a diffusing effect and masked.

to provide two signal light portions PLL and PLI, each having a distinct configuration. As shown in FIGURE 5B, light portion PLL has an arrowhead configuration similar to that of light portions DLI and DLO, illustrated in FIGURE 4B, and light portion PLE has a rectangular bar-like configuration forming a tail for the arrowhead light portion PLL.

Each alarm-intersection light module AL-DLC, FIG- URES 6A and 6B, is constructed similar to the detector and program light modules, but includes a short divider 340 which does not extend for the length of sleeve 322. Divider 340 defines two short compartments 342 and 344, which in turn respectively define alarm light portion AL and intersection `light portion DLC. Compartment 342 is filled with red dyed polyester and compartment 344 is filled with yellow dyed polyester, and the remaining portion of the sleeve is filled with clear, diffusing polyester, The top surface 346 of the module is abraded or roughened, but is not masked as in `the case of the detector and program light modules, so as to provide a circular configuration, as shown in FIGURE 6B. With this construction, light transmitted from bulbs 318 in the alarm light portion AL and intersection light portion DLC may be tinted by `the dyed polyester in compartments 342 and 344 and then be diffused through the clear polyester and displayed over the entire abraded surface 346 of the light module.

AIRCRAFT DETECTORS Referring now to FIGURE 8, there is schematically illustrated the actual runway and taxiway intersection network, which is graphically represented on the display panel DP illustrated in FIGURES 1 and 2, and, accordingly, like character references and like legends are used in FIGURE 8 for identifying like intersections and like intersection arms. Aircraft detectors LD are provided for detecting the presence of aircraft in each intersection arm. Detectors LD take the form of loop detectors which normally comprise a loop, or loops, of current carrying conductors buried below a roadway surface. The loop configuration of each loop detector LD defines a detec- -tion area so that as a vehicle, such as an aircraft, enters the detection area, an electrical disturbance occurs in fil fthe loop conductor. This -disturbance is utilized to close a set of relay contacts which remain closed so long as a vehicle is in the detection area. The detectors may also take the `form of varea sensitive, ultrasonic detectors, or spot detectors in the form of treadle pads.

As illustrated in FIGURE 8, two loop detectors LD are provided for each intersection afm, with one loop detector being located at a first detector station DS1 and a second loop detector located at a second detector station DS2. Preferably, detector station D52 is located adjacent an intersection. Detector station DS1 is spaced further from the intersection than is station DS2 so that as an aircraft Iapproaches an intersection it is first detected at station DSl and then at station D82. A pair of aircraft trafiic signals BB are located on opposite sides of each intersection arm. Preferably, as illustrated in FIGURE 8, signals BB are located with respect to detector stations DS1 and DSZ so that the signals for an intersection arm are visible to a pilot in an aircraft located at station DS1 but not visible to the pilot when the aircraft reaches station DS2.

AIRCRAFT TRAFFIC SIGNALS The aircraft traffic signals BB, shown best in FIG- URES 9 and 10, are described and claimed in Edward P. Cheslocks United States patent application, Serial No. 551,260, filed May 19, 1966, assigned to the same assignee as the present invention. Each traffic signal BB has a front diamond shaped face 348, as shown in the elevational view in FIGURE 9, and a rear diamond shaped face 350, as shown in the elevational view in FIGURE 10. As illustrated in FIGURE 9, the front face 348 of each signal BB includes four signal lenses 352, 354, 356 and 358, each of which preferably is a triangular quadrant -of a square, with the apex of each lens located at `the center of the signal face. Yellow lamps: BBLA, BBLB, BBLC and BBLD are located within the signal BB immediately behind lenses 352, 354,356 and 358, respectively. A red lamp BBLS is also located ibehind each lens. Lenses 352, 354, 356 and 358 may be transparent, with the background within the signal BB being black so Vthat when none of the lamps is energized a black diamond shaped configuration is presented by signal face 348. When one of the yellow lamps is energizedy to illuminate one of the triangular shaped lenses, the 90"l apex of that lens provides a visual directional command signal to an aircraft pilot. Thus, for example, when lamp BBLD, behind lens 358 is energized lthe 90 apex of that lens indicates to an aircraft pilot that the aircraft should proceed into an intersection and make a half right turn. A full right turn is indicated by energization of lamps BBLB and BBLC behind lenses 354 and 356, respectively, so that the 90 apex of the triangle defined yby the two lenses provides a visual directional command signal for an aircraft pilot to make a full right turn. Similarly, when lamps BBLA and BBLD are energized an aircraft pilot is presented with a visual command signal to make a full left ,turn when entering an intersection. Also, as is now evident, when both lamps BBLA and BBLB are energized an aircraft pilot is presented with a visual directional command signal to proceed straight through an intersection. Lamps BBLA, BBLB, BBLC and BBLD are selectively energized in accordance with a program entered by an airport ground traffic director, as will be described in greater detail hereinafter. All lamps BBLS are energized at the same time to provide a red diamond shaped visual command signal representative that an aircraft pilot is to stop and not proceed into an intersection until a yellow directional signal is displayed.

The rear side 350 of each traffic signal BB faces an intersection and includes a large triangular lens 360, which preferably takes the form of one-half of a square with its 90 apex pointed in an upward direction. Behind lens 360 there is provided -at least one yellow pull through lamp BBLR. Due to the large lens surface :area it may be desirable to provide two lamps BBLR, as shown in FIG- URE 10. Since the rear side 350 of traffic signal BB faces an aircraft located in an intersection, the energization of lamps BBLR serves to provide a yellow visual command signal to an aircraft pilot representative that the aircraft should pull through the intersection, i.e., proceed through the intersection, into the intersection arm at which the pull through signal lamps BBLR are energized. The lower half 362 of the rear side 350 of each traffic signal BB is prefera-bly colored black so that when lamps BBLR are energized only the upper lens 360 transmits a visual command signal to an aircraft pilot.

SYSTEM INTERCONNECTIONS Referring now to FIGURE ll, there is shown a block diagram of the systems functional and electrical interconnections. The display panel DP, best shown in FIG- URES l and 2, is electrically connected with a control console CC which includes elecrtical control circuitry. The control console CC is electrically connected with the traic signals BB, best shown in FIGURES 8, 9 and lO. The detector stations DS1 and DS2, best shown in FIG- URE 8, are electrically connected to the control console CC for relaying output signals representative of an aircrafts location on the actual network. The control conso-le CC has a first electrical feedback alarm path connected with the display panel DP for energizing alarm lamps AL, as well as an audible alarm buzzer. The control console CC also includes a second electrical feedback path connected to the display panel for purposes of energizing program lamps PL, detector lamps DL and intersection lamps DLC.

Referring now to FIGURE 8, there is illustrated a four arm intersection C having north, east, south and west intersection arms. As an aircraft approaches the intersection from the west arm, it first crosses loop detector LD associated with detector station DS1. This energizes directional lamp DLI in the control panels west arm (see FIGURE 2), indicating to a traffic director that an aircraft has been detected in the west arm and is proceeding in an easterly direction toward intersection C. The traffic director may enter a programmed route for the aircraft to proceed through intersection C 'by tracing a route with stylus S on the display panel DP, illustrated in FIGURE 2 and thence in a southward direction through the south arm. The stylus S sequentially actuates program switches PES, PS1 and PS2 in the west arm and then sequentially actuates switches PS2, PS1 and PES in the south arm. Actuation of these switches results in various program lights being energized; namely, program tail light PLE associated with the west arm indicating that an aircraft may enter the intersection from the west arm, and program lights PLE and PLL of the light module associated with the south arm indicating that aircraft may proceed from the intersection C into the south arm. Thus, energization of these lights serve as a memory for the traffic director as to the program entered. In addition, the actuation of these program switches energizes lamps BBLB and BBLC (see FIGURE 9) on the front face 348 of the traffic signals BB associated with the west arm, which provides visual directional command signals for the aircraft to enter the intersection C and make a full right turn. Actuation of the program switches in the south arm of the control panel energizes lamps BBLR on the rear side 350 of the traffic signals BB associated with the south arm, presenting visual directional command signals for the aircraft to pull through intersection C and proceed from the intersection into the south arm.

The aircraft proceeds into the intersection C actuating loop detector LD associated with detector station DS2 of the west arm. This de-energizes detector light DLI in the west arm of the display panel and energizes the intersection light DLC in the display panel at intersection C, indicating to the traf-lic director that the aircraft has left the west arm and is now present in the intersection.

As the aircraft proceeds into the south arm it crosses loop detector LD associated with detector station D52 in the south arm. This de-energizes the intersection light DLC and energizes detector light DLO associated with the south arm on the display panel, representing to the traffic director that the aircraft has left the intersection and is proceeding into the south arm. At this point, the aircraft has proceeded exactly as instructed by the route programmed yby the traffic director. If the aircraft proceeded into intersection C, as commanded by the programmed route, and continued straight ahead into the east intersection arm actuating detector station DS2 associated with the east arm, an audible alarm buzzer is energized to alert the traffic director as to the aircrafts noncompliance with the programmed route. In addition to the audible alarm, alarm lamp AL at the center of intersection C on the display panel is energized and alternately ashes on and off with a red signal indicating the location of the alarm condition. In addition to the audible and visual alarm, all red lamps BBLS (see FIGURE 9) in all traffic signals BB located at intersection C are energized until the noncompliance situation is remedied, as by radio communication with the aircrafts pilot, and the traffic director has reset the alarm.

The traffic director may change the programmed route by rerouting stylus C through the display panels illustrated network. In the event that the traffic director desires to erase the entire program, leaving the intersection with all stop lights, i.e., energization of all red lamps BBLS, this may be accomplished by actuating a program erase switch PES with the magnetic stylus S. Program switches PS1 and PS2 of each intersection arm in the display panel serve, by means of control logic circuitry, to interpret the direction traced by stylus S and energize the appropriate display panel presence lights PL and the appropriate intersection traffic signals BB. Thus, for example, if program switch PS1 is actuated before program switch PS2, the control logic circuitry enters a program representative that an aircraft is to enter an intersection from the arm associated with these program switches. Conversely, if program switch PS2 is actuated before program switch PS1 is actuated, a program is entered for an aircraft to leave the intersection through the arm associated with these program switches. The fourth magnetic reed switch DES associated with each arm, but spaced transversely away from groove 306, serves as a detector erase switch so that, when armed, it is capable of de-energizing an aircraft presence light DLI or DLO associated with that intersection arm on the display panel. Thus, for example, if aircraft presence light DLO in the south arm is energized and no aircraft is present in the area of influence of loop detector LD at detector station DS1 in the south arm of the actual network, the traffic director may extinguish this false indication by actuating the detector erase switch DES associated with the display panels south arm. The detector erase switch DES must be armed by first actuating a detector reset switch so that a true presence signal indication is not erased inadvertently.

The display panels alarm lamp AL is energized to provide a flashing red signal whenever a programming error occurs and no aircraft is involved. Such a situation occurs, for example, when a program is entered at intersection C directing an aircraft to intersection B while at the same time a program already exists at intersection B directing another aircraft toward intersection C. The reason for the visual alarm only in such a situation, is that this condition exists quite frequently when the traffic director programs a completely new route. A second type of alarm provided is both a visual and audible alarm. That is, an alarm buzzer is energized at the same time that alarm lamp AL is ashing a red signal at the center of the intersection, or intersections, involved. The audible part of this alarm is actuated whenever an aircraft is involved. The following conditions actuate this alarm:

(1) When an aircraft runs a red light, that is, if an airlcraft crosses the loop detector at detector station DSZ on its approach to an intersection when the traffic signal BB for the associated intersection arm is displaying a red signal, indicating a stop command.

(2) If a wrong turn is executed, that is, if an aircraft is given a directional command by a traffic signal BB and then enters the intersection but proceeds to leave the intersection in any direction other than the one to which the aircraft has been programmed.

(3) If a program is entered by the traffic director which would create a potential collision with a detected aircraft approaching the intersection in question; for example, if a program is entered for the west arm of the intersection Afor an aircraft to proceed to the south arm and an aircraft is yalready present in the south arm approaching the intersection.

(4) If a program is entered by the traic director that would create a potential collision, thus, for example, if the traiiic director enters a program for an aircraft to proceed from the west arm through the intersection 'and then to the south arm, and at the same time an aircraft from an interconnecting intersection is detected as leaving the connecting intersection in a northerly direction through the south arm of the programmed intersection.

Under any alarm situation; that is, whenever flashing red signal light lamp AL is energized, the appropriate traffic signals BB display all red signals at the intersection or intersections involved, stopping traffic flow. The program lights at the display panel, however, remain energized to assist the trafiic director in determining the cause for the alarm. After the alarm situation has been remedied, the traffic `director resets the alarm by means of a separate manual alarm reset switch. Once the alarms have been reset, a program may be re-entered on the intersection traffic signals BB. The manual alarm reset feature serves as an additional check on both the system and the trafiic director to insure that the alarm situation has been corrected before authorization is given to an aircraft to .proceed through the intersection in question.

The system also includes a priority circuit which serves to provide a clearance signal condition for active runways in the event that taxiways, or other active runways, cross the active runway in question. The priority circuit energizes all the traffic signals BB to display stop, i.e., red, signals for the cross traffic to the active runway in question. This circuit also energizes the active runway trafiic signals to display a yellow, i.e., go, signal when the runway is clear for use.

Although the invention has been shown in connection with a preferred embodiment, it will be readily apparent to those skilled in the art that various changes in form and arrangement of parts may be made to suit requirements without departing from the spirit and scope of the invention las defined by the appended claims.

Having thus described my invention, .I claim:

1. A panel light module `comprising:

a sleeve member;

at least one light bulb located within said member for transmitting light through one end of said member; said light bulb being completely embedded in polyester within said member in such a manner that said polyester supports said bulb in place in said member; and said sleeve member being constructed of material exhibiting light reflecting characteristics so that said sleeve serves as a light reflector.

2. A panel light module `as set forth in claim 1 wherein said sleeve material exhibits suliicient heat labsorbing characteristics to also serve as a heat sink.

3. A panel light module as set forth in claim 2 wherein ysaid sleeve member includes ya light blocking divider member, dividing said sleeve into two compartments eac-h including at least one said polyester embedded bulb.

4. A panel light module as set forth in claim 3 wherein said polyester extends for the length of said sleeve member and is roughened at said one end for a diffusing effect and masked to provide a distinctive visual display.

S. A panel light module as set forth inclaim 3 wherein said divider member extends for a length substantially equal to that of said sleeve member to provide a plurality of distinctive visual displays.

6. A detector light module comprising: a sleeve member; a light blocking divider member dividing said sleeve into two compartments, said divider member extending for a length substantially equal to that of said sleeve member; at least one light bulb completely embedded in polyester and located within each of said compartments for transmitting light through one end of said member; said polyester extending continuously for the length of each of said compartments for transmitting light through one end of said sleeve member to provide two distinctive visua-l displays.

7. A detector light module as set forth in claim 6, including means at said one end of said sleeve member defining said visual displays as two triangular shaped arrowheads having their respective apexes pointing in opposite directions.

8. A detector light module as set forth in claim 6, including mean-s `at said one end of said sleeve member defining one of said visual displays as a triangular shaped arrowhead, and ydefining the other of said visual displays as a rectangular shape representing the tail of `an arrow.

9. In combination, a display panel graphically illustrating a network of traffic paths, said panel including: an opaque sheet having grooves therein defining said network; a panel light module; a translucent sheet interposed between said panel light module and said opaque sheet and orientated in superimposed parallel relationship with said opaque sheet; said panel light module being in registry with one of said grooves, said panel light module having a sleeve member; at least one light Abulb located 'within said member for transmitting light through one end of said member and thence through said translucent sheet; said light bulb being completely embedded in polyester within said member in such a manner that said polyester supports said bulb in place in said member.

10. The combination as set forth in claim 9 wherein said sleeve member includes a light locking divider member dividing said sleeve member into two compartments, each of said compartments including at least lone said polyester embedded bul-b; said divider member extending for a length substantially equal to that of said sleeve member for providing a plurality of distinctive visual displays.

11. The combination as set forth in claim 10 where said polyester extends continuously for the length of one `of said compartments, said polyester being roughened at said one end of said sleeve member for a diffusing effect and masked to provide two distinctive visual displays.

12. The combination as set forth in claim 11 wherein said translucent sheet exhibits a light transmission characteristic on the order of 7() percent to permit observation of light from the light module, While prohibiting observation of Icomponents located beneath the sheet.

13. The combination as set forth in claim 12 wherein said sleeve member is constructed of a material exhibiting light reflecting characteristics so that the sleeve serves as ya light reflector.

14. In combination, a display panel graphically illustrating a network of trai-lic paths, said panel including: an -opaque sheet having grooves therein defining said network; a panel light module; `a translucent sheet interposed between said panel lig-ht module and said opaque sheet and orientated in superimposed parallel relationship with said opaque sheet, said translucent sheet exhibiting a light transmission characteristic on the order of 70 percent; said panel light module being in registry with one of said grooves, said panel light having a sleeve member, said sleeve member being constructed of aluminum so that said sleeve member serves as a light reflector and heat sink; a light blocking divider member dividing said sleeve member into two compartments, said divider member eXtendin-g for a Ilength equal to that of said sleeve member for providing two distinctive visual displays; at least one light bulb located within each of said compartments, said bulb being completely encapsulated in polyester within said compartment in such a manner that said polyester supports said bulb in place in said compartment, said polyester extending continuously for the length of at least one 0f said compartments for transmitting light through one end of said sleeve member7 said polyester being roughened at said one end of said sleeve member for a diffusing effect; and means at said one end of said sleeve member defining at least one of said visual displays as a triangular shaped arrowhead.

References Cited UNITED STATES PATENTS 2,247,409 7/ 1941 Roper 2408.16 2,740,957 4/1956 Davies 240-1 XR 3,194,953 7/1965 Friedland 24U- 8.16 3,206,704 9/1965 Hay l74--52.6 XR

NORTON ANSHER, Primary Examiner.

U.S. Cl. X.R. 

